Tackling invasive species across Europe

Invasive species represent one of the largest threats to biodiversity in Europe. The costs associated with the potential impacts of invasive species often stretch into the billions. A harmonised response across Europe is needed to mitigate these effects, and to ensure that policy decisions are effective.

The challenges and tools for studying biological invasions on a European level were discussed yesterday by a group of ecologists at INTECOL in London. Dr Cristina Maguas, Centre for Environmental Biology, University of Lisbon (Portugal), Dr Stefan Klotz, Helmholtz Centre for Environmental Research (Germany), and Professor James Bullock, Centre for Ecology and Hydrology (UK), outlined the challenges Europe faces in understanding and controlling invasive species in a workshop sponsored by the European Ecological Federation. Information collection, management and sharing between European nations are vital, and there are a number of tools that can be used to support this.

One of the most effective sources of information about invasive species across Europe was the DAISIE (Delivering Alien Invasive Species in Europe) inventory, which highlights that over 10000 species are non-native, and 10-15% of these will have severe ecological and economic effects. In 2008, the European Commission released a “Towards an EU strategy on invasive species” document, and is currently working on a member-wide approach to invasive species management as part of the Biodiversity 2020 targets.

Working across such diverse and wide-ranging areas can be difficult, with the ecologists at the workshop highlighting five major limitations for EU invasive species policy:
1. Variability
2. No common framework for risk assessments
3. Variable scope
4. Number of incompatible databases
5. Absence of EU policy

Participants at the workshop also highlighted that there is still much we do not understand about invasive species. Taxa other than plants and animals are understudied. Traits that make species good invaders are understood after invasion events, but using these to predict invasions is difficult, and their interactions can complicate things further.

There are major costs related with both policy action and inaction. Ecologists at the workshop stressed that the disparities between these need to be properly communicated to policy makers. Although it can often cost millions to effectively control invasive species, the economic and ecological costs of doing nothing are usually much higher. Effective strategies that may seem expensive in the short-term, could therefore lead to much greater long-term gains.